Multiple Myeloma in Dogs

Definition

• Multiple myeloma is a plasma cell tumor. Plasma cells are a specific type of white blood cell designed to create antibodies (they fight infection in the body). When a plasma cell reproduces itself in an uncontrolled manner, it develops a tumor (multiple myeloma).

  Multiple myeloma cells can cause a multitude of problems for dogs. In one such problem, the cells cause the blood to thicken, which in turn makes the heart work harder to pump the blood and can lead to heart disease or failure. In another scenario, the body works so hard to create antibodies for the tumorous cells that it cannot create them for other things, putting the dog at greater risk for other infections.

Signs and Symptoms

• Older dogs seem to be more susceptible to multiple myeloma than other animals or younger dogs. Symptoms include lethargy, weakness, increased drinking and urination, bleeding gums or noses, lameness, seizures, and even an altered level of consciousness. Broken bones can also be a symptom, because the presence of multiple myeloma in the bone marrow can weaken the bones.

Diagnosis

• If you take your dog to the vet for a multiple myeloma diagnosis, the vet will probably begin by performing blood tests on your dog. This will enable him to look for the antibodies for myeloma. He may also do an X-ray on the chest or limbs to detect the presence of the myeloma cells in the bones.

  For a definitive diagnosis, the doctor will need to biopsy the affected cells. The doctor will likely take a sample of these cells if the earlier tests he performs lead him to suspect the presence of multiple myeloma cells in your dog's body.

Treatment

• Chemotherapy is the primary treatment for multiple myeloma in dogs. For dogs, this medication is administered orally; your veterinarian will need to monitor your dog's responses to the treatment regularly as well, through urinalysis or blood tests.

  In most cases, chemotherapy works to decrease the affected plasma cell production and cure the dog. However, the disease is known to frequently relapse, so that can be expected even after successful treatment.

  Other treatments may be administered to treat the additional symptoms of multiple myeloma. Painkillers are an option if the chemotherapy does not work or if you elect not to use this procedure.

Prognosis

• According to the Michigan Veterinary Specialist website, dogs who respond successfully to chemotherapy will likely survive one to two years beyond the treatment. If your dog develops complications as a result of the disease, these complications may lower his life expectancy, depending on their severity. As a result of this prognosis, some dog owners may choose to avoid aggressive treatment and simply maintain comfort levels for the dog as he lives out the duration of the disease.